Private branched exchanges (“PBXs”) and key telephone systems have been used for many decades to provide small to large businesses with multi-line access to the public switched telephone network (“PSTN”). Typically, PBXs have been used by large companies to enable their employees to share incoming and outgoing PSTN trunk lines, so that the company does not have to dedicate individual PSTN lines to each employee. Key telephone systems, commonly referred to “key systems,” are typically smaller versions of PBXs that historically use individual lines instead of sharing anonymous trunk lines. Nevertheless, technology has all but eliminated this distinction by enabling key systems to operate within their smaller scale yet with the full functionality of modern day PBXs.
Small-to-medium sized companies may still prefer to use key systems instead of PBXs because of their cost. Technology is currently bringing together the worlds of voice and data transmissions to key systems. In addition to analogue signals, the modem key system is generally fully capable of handling digital signals as well, thus enabling it to work within a voice over internet protocol (“VoIP”) environment. Nonetheless, interconnecting today's key systems with VoIP devices typically includes re-cabling and wiring at a customer's site, which is time and labor intensive.